Forty-one years ago, in the summer heat of the state of Mississippi, three young civil rights workers were found murdered.
The victims became martyrs to the cause of civil rights
Their deaths led to nationwide outrage in America, and did much to spur the civil rights movement. The case was used as the template for the film Mississippi Burning.
But the killers were never brought to trial. Like so many white killers and abusers of blacks in Mississippi, they escaped justice because their fellow whites would never have convicted them.
On Monday, 80-year-old Edgar Ray Killen will stand trial accused of murder in Philadelphia, Mississippi, scene of the killings.
I visited a school in Philadelphia, in time for a lesson simply unthinkable 41 years ago - a civil rights lesson attended by black and white pupils and taught with vigour by a white teacher.
So what do the pupils think of the trial of Edgar Ray Killen, a trial which reopens the wounds of this small town?
"I think they should go after them because even though it was a long time ago it still doesn't justify the fact of what they did," says one child.
"I do know that later, if he doesn't repent of his sins, he will be dealt with by God," says another.
But a third adds: "People that bring this trial back will bring back... bad things."
It is certainly true that the killing of the three civil rights workers took place a long, long time ago.
It was a time when the country roads around Philadelphia were dangerous places for the young volunteers who came to this state to try to help black people register to vote in the teeth of fierce opposition from local whites including the police.
David Kendall has a smart office a million miles from here in Washington DC, where he is Bill Clinton's lawyer, but back in 1964 he shared a room with one of the murder victims and remembers being frightened for his life every day.
"I think the most frightened I ever was when I was stopped by the police one Sunday morning and a guy got out of the car.
"He was plainly going to church, he had a suit and tie on, he was white, about 50. He sort of leaned in, looked at me and said: 'You know, the Tallahatchie river ain't full yet.'
"Now the way he said it doesn't sound particularly scary now - it is the most frightened I've ever been."
Back in the main street of Philadelphia, across from the courthouse where the trial of Edgar Ray Killen will take place, is Ray Gray's barber shop.
Mr Gray cuts the hair of the old timers, most of whom regard Mr Killen as the victim.
"Well he's just a good man, he enjoys talking and I think that's mainly what got him into the trouble he's in."
Asked whether he thinks Mr Killen is guilty of doing anything wrong, he answers quickly: "I don't think he would be."
There are many, many victims for whom justice has been permanently denied
And what of the man himself?
Edgar Ray Killen is maintaining that he is innocent and telling reporters that his conscience is clear.
"I have no doubt I am at peace with God - I wish I was at peace with the world as much as I am with God."
Mr Killen's defiance and the support he gets from many whites of his generation does not make for reconciliation, however much time has passed.
Clint Collier was a civil rights leader in Philadelphia, and at the age of 90 still burns with rage when the trial of Edgar Ray Killen is mentioned.
"This situation we've got here now - they could've solved that 40 years ago.
Why didn't they? Your white race. Why didn't they?"
Mr Collier's point is that a few fancy trials years later do not begin to atone for the history of this state.
This area of Mississippi is surrounded by swamps. When they dredged around Philadelphia looking for the bodies of the three civil rights workers they found several corpses of unidentified black men - killed and dumped.
There are many, many victims for whom justice has been permanently denied.